What is the best way to align a roomscale VR scene to the headset position on load?

I have a multiscene game with a main scene and some portals into different rooms (scenes).
What I want to achieve is that the player faces “north” upon loading a scene - regardless of where he is looking at in the real world.

Right now all scenes are loading “north” in respect to the PlayArea. But when a player looks “south” in the real world that is where he is facing upon starting in a new scene.

My next step would be to put the complete scene “architecture” in to an object and rotate it according to the player orientation on start. It seems a bit inelegant but if its the only way - how would my SceneArchitectureObject get only the horizontal player rotation? (I’m still learning C# and often miss the obvious)

(Using SteamVR, VRTK, TheLabRenderer)

It’s probably better to put the player object inside a container and move that instead of moving the rest of the scene. On startup you could get the initial rotation of the camera and set the rotation of the container to the inverse.